i just recently cracked my transmission.
i have two 4in cracks pretty thin but enough to leak out quite a bit when running in gear.
i was wondering it was possible to just weld the cracks closed or anything or do i have to just replace the tranny?

 

You would need to take the tranny apart and remove all the fluid first. Then you can weld it.....maybe drill at the end of each crack then fill it while welding to stop the cracks from spreading too

 

proper crack repair calls for drilling a hole through the ends of the crack,


then use single cut bur bit to grind a groove throughout the whole length of the crack..


make sure the case is cleaned really well...
then you are ready to weld it..

 

buy a new case. They are fairly cheap.

 

The biggest problem is oil contamination in the crack. Without taking the whole thing apart and thoroughly cleaning the case, then grinding, preheating, welding, etc. It is probably easier to get a new case.

 

You could give it a shot but the cracks sound to be pretty big.. A lot times when you weld that much on cast aluminum It'll put so much stress on the metal it will crack somewhere else when it's cooling.. even if you slow cool...

 

mine cracked 2 a while back,i drilled, cleaned it, preheated it,and then tiged the outside of the case,and then wire welded the inside, ran the tranny for about 3 hours stomped it spun threw 2nd in2 3rd, got home tranny fluid everywhere,so got a gsr case and put my si gears in it,so do yourself a favore and just go get you a new case, and before you say ima noweldin bitch i do it everyday 4 a living and make good money doin it

 

I have fixed a few tranny cracks before. I just clean and weld, never had had a problem.

Adriano

 

i guess it just depends on where the crack is,mine was rite beside the axle seal on the passenger side,I think that was the reason mine cracked again, because of wheel hop,no traction bars,if it was just in the middle of the tranny, it would have probly been alit, I had a cracked ls tranny i welded and ran 4 a year and a half,but still would have been in best of intrest to get a nother case,you can find a case 4 it pretty reasonable if u look

 

I'd say it depends on how old/dirty the case is. The aluminum is cast and is porous and soaks up any contaminants and when you go to weld it, guess where all those contaminants go, right in your weld pool. It's worse when you weld cast aluminum when it's in the cooling system, as soon as you put heat to it, the antifreeze seeps out of the aluminum. I'd heat the case up to about 400 degrees then weld it while it's still hot. Good luck.